Chronic sinusitis (CS), an inflammatory condition of the sinuses, is a common syndrome, with estimates of prevalence as high as 13% in Western populations. This condition is characterized by any combination of specific symptoms including nasal congestion, decreased or lost sense of smell, anterior and/or posterior nasal discharge, facial pain, and/or headache and consequences thereof, often for a period of years. CS can be clinically divided into CS with or without nasal polyps.
Nasal polyposis (NP) is a clinical condition characterized by the presence of multiple polyps in the upper nasal cavity, originating from the osteomeatal complex. NP is a T helper cell-2 (Th-2) driven inflammatory process affecting the mucosa of the nose and paranasal sinuses. Eosinophils and their products are thought to be a hallmark of nasal polyp-associated inflammation as elevated levels of interleukin-5 (IL-5; promotes eosinophil survival and differentiation), eosinophil cationic protein (ECP), and eotaxin (eosinophil chemoattractant), factors that attract and activate eosinophils, are typically found in nasal polyps. Eosinophils are the predominant inflammatory cell found in the sinuses and nasal polyps, and nasal polyps are also associated with elevated levels of IgE. NP is characterized by long-term symptoms of nasal obstruction and congestion, reduction in or loss of sense of smell, anterior and posterior rhinorrhea, and facial pain. Current treatment options range from local or systemic corticosteroids to functional endoscopic sinus surgery.
Current medical management of chronic sinusitis with nasal polyps/nasal polyposis (CSwNP) primarily focuses on controlling inflammation, which involves administration of topical and systemic corticosteroids with a goal of reducing polyp mass and number. In case of failure, surgical excision is indicated. However, disease recurrence is reported to be frequent after surgery, with rates of recurrence approaching 50% in patients with tissue eosinophilia.